Subtypes Research Articles

An update on the distribution of Blastocystis subtypes in the Americas

Blastocystis is an intestinal protist that presents worldwide distribution, colonizes animal and human hosts, and is classified into at least 34 ribosomal subtypes (STs). Herein, we conducted an update based on studies reporting Blastocystis-positive samples obtained from diverse hosts in the Americas. We described the distribution throughout the continent by assembling maps representing the distribution of STs and the most important 18S-rRNA alleles. Thirty-nine articles from the previous study, “A summary of Blastocystis subtypes in North and South America,” and forty-one additional articles from March 2019 to March 2022 were considered. The most common subtype described was ST3, representing the highest percentage of positive samples. Other recently identified STs include ST12, ST13, and ST16 in humans, and ST10, ST14, and ST17 in animals. Novel subtypes have also been described in this continent. We assembled and updated the distribution of Blastocystis in the Americas. We hope this delivers new understandings and knowledge of this microorganism’s prevalence and genetic diversity.

Levels of Genetic Variants Among Symptomatic Blastocystis Subtypes and their Relationship to Mucosal Immune Surveillance in the Precancerous Colons of Experimentally Infected Rats

PurposeThe relationship between the genetic diversity of Blastocystis and immune surveillance in precancerous colons with blastocystosis is still under investigation. This study aimed to identify the genetic Blastocystis variants among 54 symptomatic human isolates and their relationship to mucosal immune surveillance in the precancerous polyps of experimentally infected rats.MethodsPolymerase chain reaction and high-resolution melting (PCR/HRM) curves discriminated human symptomatic Blastocystis isolates into subtypes (STs)/intrasubtypes, which were orally administered to rats to induce experimental infection. Then, the mucosal immune responses of the infected colons were evaluated in relation to polyp formation through immunostaining to identify mucus MUC2 and determine mucosal immune cell (goblet, lymphocyte and mast) counts, secretory IgA levels and parasitic intestinal invasion.ResultsST1, ST3, and ST4 were found in 18.5% (10/54), 54.7% (29/54), and 27.8% (15/54) of the samples, respectively. Then, the HRM curve discriminated ST3 into the wild, mutant, and heterozygous [17/54 (31.5%), 5/54 (9.3%), and 7/54 (12.9%)] intrasubtypes. ST1 and ST4 had no genetic variations. Precancerous polyps were detected in the colons of 40.5% of the infected rats. ST1 constituted 14.7% of these cases, while the wild, mutant, and heterozygous intrasubtypes of ST3 showed polyps in 12.9%, 5.5%, and 5.5% of cases, respectively. Only 1.9% of the polyps were related to ST4. MUC2 showed weak immunostaining in 44.5% of the infected colons, and 38.9% were polyp inducers. Low goblet cell numbers and high interepithelial lymphocyte counts were significantly associated with polyp formation, particularly with ST1 and wild ST3. Among the polyp inducers, high numbers of mast cells were detected in wild ST3 and ST4, while a low number was found with heterozygous ST3. The level of secretory IgA was low in polyp-inducing STs. Most of the results were statistically significant.ConclusionImmunosurveillance showed a potential relationship between ST1 and the ST3 intrasubtypes and precancerous polyps. This relationship may provide insight into the prevention and/or development of new immunotherapeutic strategies to combat colorectal cancer.

Resistance of Blastocystis to chlorine and hydrogen peroxide

Blastocystis is a ubiquitous, widely distributed protist inhabiting the gastrointestinal tract of humans and other animals. The organism is genetically diverse, and so far, at least 28 subtypes (STs) have been identified with ST1–ST9 being the most common in humans. The pathogenicity of Blastocystis is controversial. Several routes of transmission have been proposed including fecal–oral (e.g., zoonotic, anthroponotic) and waterborne. Research on the latter has gained traction in the last few years with the organism having been identified in various bodies of water, tap water, and rainwater collection containers including water that has been previously filtered and/or chlorinated. Herein, we assessed the resistance of 11 strains maintained in culture, spanning ST1–ST9 to various chlorine and hydrogen peroxide concentrations for 24 h, and performed recovery assays along with re-exposure. Following the treatment with both compounds, all subtypes showed increased resistance, and viability could be visualized at the cellular level. These results are hinting at the presence of mechanism of resistance to both chlorine and hydrogen peroxide. As such, this pilot study can be the platform for developing guidelines for water treatment processes.

Prevalence, Subtype Distribution and Zoonotic Significance of Blastocystis sp. Isolates from Poultry, Cattle and Pets in Northern Egypt.

Blastocystis sp. is a widespread enteric protozoan that frequently infects human and animal groups. Despite its burden and zoonotic potential worldwide, epidemiological investigations remain limited in animal groups that come in contact with humans. Therefore, the largest survey ever conducted in North Africa was performed in Egypt with the aim to investigate the prevalence and subtype (ST) distribution of Blastocystis sp. in animals. For this purpose, a total of 889 fecal specimens were collected from chickens (217), cattle (373), dogs (144) and cats (155) from six governorates of northern Egypt. These specimens were then screened for the presence of Blastocystis sp. using a quantitative real-time PCR, followed by subtyping the isolates. The overall prevalence of Blastocystis sp. reached 9.2% (82/889), with the highest infection rates reported in chickens (17.0%) and domestic cattle (11.0%), highlighting an active circulation of the parasite in both animal groups. In contrast, the low prevalence in cats (2.6%) and the absence of the parasite in dogs suggested that pets are not natural hosts of Blastocystis sp. ST10 and ST14 were largely predominant in cattle, confirming that both STs represented cattle-adapted STs. The report of one ST3 and one ST4 isolate in this animal group could be explained by an accidental zoonosis from humans to animals. All but one of the subtyped isolates in poultry belonged to ST7, which was considered as an avian ST. The presence of a remaining isolate of ST14 likely reflected a transient infection from contact between birds and cattle feces. The same environmental contamination was also likely the source of the ST14 infection in three of the four positive cats, with the remaining animals infected by ST3 as the result of human-to-animal transmission. These occurrences and subtyping data, combined with those previously collected in the Egyptian population, implies that poultry could play a significant role as reservoir for zoonotic transmission, which would not be the case for cattle and pets.

Subtypes and phylogenetic analysis of Blastocystis sp. isolates from West Ismailia, Egypt

In Egypt, Blastocystis sp. is not yet on the diagnostic list of parasitology reports, and information about its subtypes (STs) is scarce. This study investigated its prevalence and its STs/alleles, performed phylogenetic analysis, and considered the distribution of risk factors associated with Blastocystis sp. infections in West Ismailia, Ismailia governorate. Sociodemographic data, exposure factors, and previous parasitic infection status were recorded for symptomatic and asymptomatic individuals. Microscopy, polymerase chain reaction, sequencing, and phylogenetic analysis for Blastocystis sp. isolated from fecal samples were performed. Eighty Blastocystis sp.-infected individuals (15.3%) were examined. The age of the individuals ranged between 0.60 and 85.0 (mean 17.10 ± 15.70), the male/female ratio was 33/47, and the asymptomatic/symptomatic ratio was 55/25. The findings demonstrate clear evidence of direct contact with animals, poor water quality, and previous parasitic infections. Eleven samples yielded three Blastocystis STs (ST1: allele 4, ST2: alleles 9 and 12, and ST3: allele 34), with ST3 (45.5%) representing the most common subtype. Phylogenetic analysis with a robust bootstrap revealed three distinct clades for isolates of each subtype. This study updates the epidemiological knowledge of the distribution of Blastocystis sp. STs in Egypt and expands the current understanding of the prevalence, risk factor frequencies, and genetic diversity of this protist in the studied area.

CC16 polymorphisms in asthma, asthma subtypes, and asthma control in adults from the Agricultural Lung Health Study

BackgroundThe club cell secretory protein (CC16) has anti-inflammatory and antioxidant effects and is a potential early biomarker of lung damage. The CC16 single nucleotide polymorphism (SNP) rs3741240 risk allele (A) has been inconsistently linked to asthma; other tagging SNPs in the gene have not been explored. The aim was to determine whether CC16 tagging polymorphisms are associated with adult asthma, asthma subtypes or asthma control in the Agricultural Lung Health Study (ALHS).MethodsThe ALHS is an asthma case-control study nested in the Agricultural Health Study cohort. Asthma cases were individuals with current doctor diagnosed asthma, likely undiagnosed asthma, or asthma-COPD overlap defined by questionnaire. We also examined asthma subtypes and asthma control. Five CC16 tagging SNPs were imputed to 1000 Genomes Integrated phase 1 reference panel. Logistic regression was used to estimate associations between CC16 SNPs and asthma outcomes adjusted for covariates.ResultsThe sample included 1120 asthma cases and 1926 controls of European ancestry, with a mean age of 63 years. The frequency of the risk genotype (AA) for rs3741240 was 12.5% (n = 382). CC16 rs3741240 was not associated with adult asthma outcomes. A tagging SNP in the CC16 gene, rs12270961 was associated with uncontrolled asthma (n = 208, ORadj= 1.4, 95% CI 1.0, 1.9; p = 0.03).ConclusionThis study, the largest study to investigate associations between CC16 tagging SNPs and asthma phenotypes in adults, did not confirm an association of rs3741240 with adult asthma. A tagging SNP in CC16 suggests a potential relationship with asthma control.

Identification of Immunogenic T and B-Cell Epitope Peptides of Rubella Virus E1 Glycoprotein towards the Development of Highly Specific Immunoassays and Vaccine

Introduction: The Rubella virus has a worldwide occurrence and congenital Rubella syndromes are widely recognized as an emerging infection in several parts of the world. Miscarriage, perinatal mortality, and stillbirth can develop in pregnancy during the first trimester. The most frequent techniques for laboratory diagnosis of Rubella virus infection are IgM and IgG-based serological detection methods. Such emerging viral and bacterial pathogen emphasizes the development of fast diagnostic devices; there is a need for enhanced and quicker methods.
 Materials and Methods: Search for peptide vaccine with specific T and B-cell epitopes was identified through bioinformatics-based approaches. These were identified utilizing available Rubella virus E1 glycoprotein sequence databases. The outer-membrane glycoprotein, E1 is a target protein for the prediction of best antigens.
 Results: Using BepiPred2 program, the potential B-cell epitope PFCNTPHGQLEVQVPPDPGD with high conservation among E1 glycoprotein of rubella virus and the maximum surface exposed residues was identified. Using IEDB, NetMHCpan, and NetCTL programs, T-cell epitope RPVALPRAL was identified. Predicted epitopes were found to have promiscuous class-I major histocompatibility complex binding affinity to major histocompatibility complex super types, antigenicity scores, and high proteasomal cleavage. The three-dimensional modeled structures were created using I-TASSER online server for highlighting the predicted T- and B- cell epitopes.
 Conclusion: The predicted T and B cell epitope could be used for the development of immunoglobulin assay and vaccine candidate peptide.

Detection of Blastocystis Subtypes in Children with Functional Abdominal Pain and Celiac Disease in Çorum, Turkey.

Blastocystis has been associated with various symptoms of the gastrointestinal tract. We aimed to investigate the prevalence of Blastocystis in children with celiac disease (CeD) or functional abdominal pain (FAP) and to evaluate its subtypes (STs) with respect to demographic, socioeconomic and epidemiological factors. Overall, 161 fecal samples were collected from healthy children and patients with FAP or CeD in Hitit University Erol Olçok Research and Training Hospital, Corum, Turkey between 2016-2018. Samples were examined using both native-Lugol (NL) and trichrome-stained (TS) smears, and further analyses by PCR and Sanger sequencing were performed. A standard questionnaire was applied to obtain demographic, socioeconomic, epidemiological data. Blastocystis was found in 10.6% of the total study population. Neither bacteria nor any other parasites were found, except for one Giardia (0.6%) in the CeD group. The presence/absence of the parasite was not found to be associated with demographic, socioeconomic and epidemiological factors. Blastocysis was detected in 11.5% (6/52) of the CeD, 7.7% (4/52) of the FAP, and 12.3% (7/57) of the healthy group. Diagnostic methods were similar in terms of Blastocystis detection (P= 0.671), and there was fair agreement between the NL, TS and PCR (Fleiss' Kappa=0.847, P=0.001). ST2 (42.8%) and ST3 (35.7%) were the predominant STs followed by ST1 (21.4%). We observed no difference between study groups in terms of Blastocystis prevalence. ST1, ST2 and ST3 subtypes were detected. Blastocystis prevalence and STs were not related to any of the demographic, socioeconomic and epidemiological factors.

Whole-genome sequencing-based characteristics of Escherichia coli Rize-53 isolate from Turkey.

Urinary tract infections (UTIs) are one of the most common infectious diseases. Inappropriate and excessive administration of antibiotics has led to the increased antibiotic resistance in the pathogens that cause UTIs. This work focused on identifying genetic determinants of antibiotic resistance in a clinical isolate of UTI-causing Escherichia coli. A clinical isolate of E. coli resistant to β-lactam, tetracycline and aminoglycoside antibiotics was analyzed using whole-genome sequencing (WGS) to identify genes that contribute to its resistance. The clinical isolate was obtained from a urine sample of a UTI patient in Turkey and identified via 16S rDNA sequencing. Antimicrobial susceptibility test was performed for 17 antibiotics using VITEK® 2 and the results were confirmed using minimum inhibitory concentration assay. Whole-genome sequencing of the isolate was performed using Illumina sequencing and analyzed with bioinformatic tools for multilocus sequence typing, replicon types, virulence factors, and antimicrobial resistance genes. Whole-genome datum was submitted to the National Center for Biotechnology Information (NCBI; accession No. JAKSGM000000000). The isolate was only found to be resistant to piperacillin in the β-lactam class of antibiotics. While the isolate was also resistant to aminoglycoside and tetracycline antibiotics, it was sensitive to other antibiotics tested. Ten antibiotic resistance genes were identified in the genome of the isolate: blaOXA-1, blaOXA-2, aac(6')-II, aac(6')-Ib-cr, tetB, catB3, qacE, sitABCD, mdfA, and sul-2. Clonal subtype (ST) and serotype of the isolate were identified as ST2141 and O107/H39, respectively. Plasmid replicon typing was used to identify 5 plasmid types in the genome of E. coli Rize-53 (Col(BS512), IncC, IncIA, IncFIB(AP1918), and IncFII(pRSB107)); however, none of the resistance genes were encoded on the plasmid. Genetic determinants of resistance to tetracycline, β-lactam and aminoglycoside antibiotics were identified using WGS in a uropathogenic E. coli from ST2141 lineage and O107:H39 serotype, isolated in Turkey.

Molecular Detection and Genetic Diversity of Blastocystis in Korean Dogs.

Blastocystis is a genus of unicellular heterokont parasites belonging to a group of organisms known as Stramenopiles, which includes algae, diatoms, and water molds. Blastocystis includes several species that habitat in the gastrointestinal tracts of organisms as diverse as humans, farm animals, birds, rodents, reptiles, amphibians, fish, and cockroaches. It is important to public health and distributed globally, but its prevalence in dogs in Korea has not been reported to date. Here, we collected 787 canine fecal samples and assessed Blastocystis infection by age, sex, region, season, and diarrhea symptoms. We determined Blastocystis subtypes using phylogenetic analyses based on 18S rRNA gene sequences. We identified, 10 Blastocystis positive samples (1.3%). A higher proportion of infected dogs was asymptomatic; however, infection rates did not significantly differ according to region, age, sex, and season. Phylogenetic analysis showed that the Blastocystis sp. identified belonged to 4 subtypes (STs), ST1, ST5, ST10, and ST14, thus revealed the genetic diversity of Blastocystis sp. in dogs Korean. This is first report on the presence of Blastocystis sp. in dogs Korean. This study revealed a lower infection rate than expected and differed from previous studies in STs. Further studies are warranted to observe the national infection status of Blastocystis in dogs and the genetic characteristics of this genus.

A Multivariate-Based Provably Secure Certificateless Signature Scheme With Applications To The Internet Of Medical Things

Abstract Over the last few years, Internet of Medical Things (IoMT) has completely transformed the healthcare industry. It is bringing out the most notable, and unprecedented impacts on human health, and has totally changed the way we look at the healthcare industry. The healthcare sector all around the globe are leapfrogging, and adopting the technology, helping in transforming drastically in a very short span of time. However, as more and more number of medical devices are being connected to IoMT, security issues like ensuring authenticity and integrity of the transmitted data are also on the rise. In view of the context, there is a need of an efficient cryptographic primitive that can address these issues in a viable manner. A signature scheme seems to be the natural choice to mitigate the security concerns. But, traditional signature schemes, both public-key-infrastructure-based and Identity-based, have their own disadvantages, which makes them unsuitable for IoMT networks. Thus, to address the security issues and problems like certificate management and key escrow, herein, we put forward the first multivariate-based certificateless signature scheme, namely, Multivariate Certificateless Signature (Mul-CLS), which is built on top of the intractability of multivariate-quadratic (MQ) problem. The fact that multivariate public key cryptosystem provides fast, post-quantum safe and efficient primitives makes it a front-runner candidate among the other post-quantum cryptography candidates. Our scheme Mul-CLS provides existential unforgeability against chosen message and chosen identity Super Type I and Super Type II adversary if solving the MQ problem is NP-hard. In addition to that, our proposed Mul-CLS presents itself as a robust and cost-friendly cryptographic building block for building IoMT networks.

Main Production Methods for Steels of Super Duplex 25Cr Type and Features of Technology for Their Production Under Zlatoust Metallurgical Plant Conditions

Main Production Methods for Steels of Super Duplex 25Cr Type and Features of Technology for Their Production Under Zlatoust Metallurgical Plant Conditions

The Role of Inhabited Animals With People in Human Transmission of Blastocystis sp.

Blastocystis sp. is a common intestinal parasite worldwide that can cause infection in humans and animals. Blastocystis sp. has a high genetic diversity with 17 different subtypes (ST) identified to date. Since nine of these subtypes are common in both humans and animals, it has been proposed that animals may have a role in the transmission of Blastocystis sp. to human.
 The aim of this study is to investigate the epidemiological effect of animals on the human transmission of Blastocystis species by molecular methods for in our country.
 A total of 420 faecal samples were collected from the cattle, sheep, dogs, horses and chickens. Samples were stained with trichrome staining and cultivated by Jones's medium culture method. Blastocystis was detected in 53(12.6%) of 420. The samples were examined by Polymerase Chain Reaction (PCR) to identify nine common human subtypes.
 Subtypes were not detected in 33(62.3) of the 53 Blastocystis positive samples. Subtypes were detected in 20(37.7%) samples. The detected subtypes were as follows: ST5 in 4(7.5%) sheep, ST6 in 6(11.3%) chickens, ST7 in 11(20.7%) chickens, both ST6-ST7 were detected in one chicken).
 ST1, ST2, ST3 and ST4 - common subtypes in our country- were not detected in any animal. Sheep and chickens may be the source of human transmission of ST5, ST6 and ST7, the rare subtypes in our country. 
 As a result, humans rather than animals, seem to be the source of the human transmission of Blastocystis sp. in our country.

Numerical Investigation of the Effect of Trailing Edge Shape on Surface-Piercing Propeller Performance

One of the main challenges in the development of surface-piercing propellers is to identify the effects of geometric parameters on the performance. The main geometric difference between SPP and conventional propellers is its blade section shape. The blade section is of super cavity type with a sharp leading edge and thick trailing edge. The geometry of this propeller is mostly designed experimentally, and comprehensive studies have not been performed to examine its parameters. Therefore, this research aims to investigate the effect of trailing edge shape on ventilation cavity development and SPP performance. The performance of a series of HL-tx propellers consisting of 6 propellers with different trailing edge shapes has been studied numerically. Numerical simulation of geometries was performed using URANS method coupled with the VOF method to capture the interface of fluids. The sliding mesh technique was also used to simulate the rotation of SPPs in transition mode. The results of the simulation method are in good agreement with the experimental data. As the results indicated, there was a 40% change in thrust and torque coefficients due to the trailing edge shape changes, which is a significant effect. However, changes in efficiency are about 7%. Meanwhile, the results revealed SPPs with a larger angle to the chord line and shorter height have better performance and ventilation cover behind the blade.

Distribution, genetic diversity, and zoonotic significance of Blastocystis subtypes in pet dogs

The common intestinal protist, Blastocystis sp., is a highly frequent parasitic agent in human and animal fecal samples, globally. The current study evaluated the prevalence of this parasite and involved subtypes (STs) in examined pet dogs in Shiraz, southwestern Iran. A number of 100 fresh fecal specimens were randomly collected from pet dogs referred to the veterinary clinics and pet shops in Shiraz during July 2021-January 2022. The genomic DNA was extracted from fecal samples and a conventional PCR was performed. Next, sequencing of the positive samples was done based on the small subunit ribosomal rRNA gene. The results showed that 5 % (5 out of 100) of the examined samples were positive for Blastocystis. As anticipated, three known Blastocystis subtypes with zoonotic concern, ST1 (60 %, n = 3), ST2 (20 %, n = 1) and ST3 (20 %, n = 1), were characterized. Based on phylogenetic analysis, these subtypes showed 100% identity with their reference counterparts. In conclusion, the zoonotic subtypes found in pet dogs in Shiraz can pose a drastic challenge to their pet owners and other domestic animals. Albeit the role of dogs as a potential natural reservoir of Blastocystis sp. stays unknown, it appears that these animals could represent possible reservoirs of zoonotic transmission of Blastocystis sp. Still, there is paucity of data on the epidemiology of Blastocystis and its subtypes in dogs in Iran.

Molecular Epidemiology and Subtype Distributions of Blastocystis Sp. in Humans and Non-Human Primates

Blastocystis sp. is an intestinal protozoan that could infect human and many other non-human mammal hosts worldwide. It is estimated that there are currently more than one billion infections in humans, however the importance of public health is still remain controversy. In the recent years, various molecular epidemiological studies have been applied in the world to identify subtypes of Blastocystis sp., due to its remarkable genetic diversity. Blastocystis sp. isolates from humans and animals have been divided into 22 subtypes (STs) based on the phylogeny of small subunit rRNA genes (SSU rDNA). In this review, we investigated the molecular epidemiology and assessed the subtype distributions of Blastocystis sp. in humans and non-human primates (NHPs). These findings will update the epidemiology and subtype of Blastocystis sp., and it will help to understand the current subtypes and zoonotic potential of Blastocystis sp.

Rare Occurrence of Blastocystis in Pet Animals and Their Owners in the Pomeranian Voivodeship in Poland in the Light of Literature Data.

Blastocystis is an intestinal microeukaryote with ambiguous pathogenicity, commonly detected in human feces worldwide. It comprises at least 28 genetically diverse subtypes (STs), 12 of which also occur in a wide range of animal species, giving rise to suspicion of zoonotic transmission. To investigate this, we conducted a molecular study of 145 stool samples of pet animals, and 67 of their owners, living in an urban area in Poland. Blastocystis was detected in only three (2.1%) animal samples (of two bearded agamas and a leopard gecko), while all dogs, cats, and pet rodents were Blastocystis-negative. Blastocystis was also present in three (4.5%) owners of animals, but they were cat owners, not reptile owners, and the subtypes identified in them differed significantly from those of reptiles. Additionally, the frequency of Blastocystis in different groups of dogs (depending on how they were kept) was analyzed. This work is the first to find Blastocystis in pet reptiles, and we encourage further investigation of Blastocystis in this poorly examined group of animals, as well as continued study on the transmission of this microorganism between humans and animals.

Genetic diversity of Blastocystis subtypes in the Alpine musk deer (Moschus chrysogaster) in Gansu province, northwestern China.

Blastocystis sp. is a gastrointestinal pathogen that is frequently found in humans and animals worldwide. In this study, 201 fecal samples were collected from captive Alpine musk deer (Moschus chrysogaster) at three farms in Gansu province. Blastocystis was detected and subtyped by amplifying and sequencing the small subunit ribosomal DNA gene. The overall prevalence of Blastocystis was 39.8% (80/201). Five known Blastocystis subtypes (STs), including ST1 (n=1), ST4 (n=12), ST10 (n=50), ST14 (n=6), and ST24 (n=11) were identified using subtyping and evolutionary analysis. ST10 was the most common ST observed in each farm. This study showed the infection status and genetic characteristics of Blastocystis in M.chrysogaster. Based on the surveyed data, because various potentially zoonotic STs, such as ST1, ST4, ST10, ST14, and ST24, were detected, it is believed that the zoonotic risk of Blastocystis from the Alpine musk deer in this area cannot be ignored.

Evaluation of association with subtypes and alleles of Blastocystis with chronic spontaneous urticaria

Blastocystis is a single-celled parasite commonly found in humans and its pathogenic role is still controversial. In recent years, some studies have suggested that Blastocystis may be a possible agent of gastrointestinal and dermatological symptoms such as acute or chronic urticaria, angioedema, rash, itch, palmoplantar, and diffuse pruritus. We aimed to investigate whether there is a relationship between Blastocystis subtypes and alleles in patients with chronic spontaneous urticaria (CSU) as a case-control study. In this study, stool samples were collected from patients with CSU (n=135) and healthy individuals (n=54). The presence of Blastocystis was investigated using the direct saline smear, Lugol's iodine staining, trichrome staining, Jones’ medium culture and PCR assays in stool samples and subtypes (STs) were determined by sequencing according to DNA barcoding. The presence of Blastocystis was identified in 30.4% (64/210) the stool samples, including 31.9% (43/135) of the patients with CSU and 14.8% (8/54) of the control group. Moreover, it was found statistically significant the presence of Blastocystis in terms of both groups (p<0.018). ST3 was detected in 45.9% and 62.5 % as the most prevalent subtype the patients with CSU and the control group, respectively. ST1 (18.9%), ST2 (27%) and ST7 (8.1%) was identified in the patients with CSU group. There was no statistically significant correlation between Blastocystis subtypes and both the groups (p<0.240, p<0.323). Allele 4 for ST1; alleles 9, 10, 11 and 12 for ST2; alleles 34, 36 and 38 for ST3; alleles 41 and 101 for ST7 were detected. Allele 34 (ST3) was found significant in the patients with CSU as compared with control group (p<0.020). Moreover, statistically significant association was found between total IgE value and the certain subtypes (ST2 and ST3) (p<0.0001). As a result of this study, the presence of Blastocystis ST3 allele 34 significantly associated with chronic spontaneous urticaria was revealed.

Subtype analysis and prevalence of mixed subtype infection of Blastocystis in farmed pigs from Chiba Prefecture, Japan

Blastocystis is an intestinal eukaryote found globally in humans and a wide range of animals. Blastocystis has been reported in domestic pigs, with subtype (ST) 5 being the most dominant, followed by ST1 and ST3. PCR-sequencing is commonly used for ST identification in pigs, but it often results in an underestimation of the prevalence of mixed infections. Here, we aimed to investigate the ST distribution and prevalence of mixed ST infections of Blastocystis in pigs from Chiba Prefecture in eastern Japan. A total of 82 fecal samples positive for Blastocystis were collected from two different farms, A and B. PCR was performed using ST-specific primers for ST1, ST2, ST3, and ST5. The prevalence of single ST5 infections was 37.8% (31/82), whereas that of mixed infections with ST5 and other STs was 57.3% (47/82) . A high percentage of single ST5 infections was observed in sows, piglets, and weaners from farm A (13/15, 86.7%), whereas mixed infections of ST5 and other STs (ST1 and ST3) were observed in 3- to 5-month-old grower pigs (15/18, 83.3%). Similarly, in farm B, most sows and piglets under 1 month of age showed a single ST5 infections (12/17, 70.6%), whereas weaner, grower, and finisher pigs showed mixed infections with ST5 and other STs, including ST1, ST2, and ST3 (27/28, 96.4%). In domestic pigs, diet and rearing environments change dramatically over the course of the animal's lifetime, which may have caused this difference in the prevalence of mixed ST infections among different age groups.